/***
 * Copyright 2002-2010 jamod development team
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ***/

package net.wimpi.modbus.procimg;

import net.wimpi.modbus.util.Observable;

/**
 * Class implementing an observable register.
 * 
 * @author Dieter Wimberger
 * @version @version@ (@date@)
 */
public class ObservableRegister extends Observable implements Register {

	/**
	 * The word (<tt>byte[2]</tt> holding the content of this register.
	 */
	protected byte[] m_Register = new byte[2];

	public int getValue() {
		return ((m_Register[0] & 0xff) << 8 | (m_Register[1] & 0xff));
	}// getValue

	public final int toUnsignedShort() {
		return ((m_Register[0] & 0xff) << 8 | (m_Register[1] & 0xff));
	}// toUnsignedShort

	public final synchronized void setValue(int v) {
		m_Register[0] = (byte) (0xff & (v >> 8));
		m_Register[1] = (byte) (0xff & v);
		notifyObservers("value");
	}// setValue

	public final short toShort() {
		return (short) ((m_Register[0] << 8) | (m_Register[1] & 0xff));
	}// toShort

	public final synchronized void setValue(short s) {
		m_Register[0] = (byte) (0xff & (s >> 8));
		m_Register[1] = (byte) (0xff & s);
		notifyObservers("value");
	}// setValue

	public final synchronized void setValue(byte[] bytes) {
		if (bytes.length < 2) {
			throw new IllegalArgumentException();
		} else {
			m_Register[0] = bytes[0];
			m_Register[1] = bytes[1];
			notifyObservers("value");
		}
	}// setValue

	public byte[] toBytes() {
		return m_Register;
	}// toBytes

}// class ObservableRegister
